EWING, N.J.--(BUSINESS WIRE)--Antares Pharma, Inc. (NASDAQ: ATRS) today announced the submission of a New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) for OTREXUP™, a combination product for the delivery of methotrexate (MTX) using Medi-Jet™ technology. OTREXUP was developed for easy subcutaneous administration of MTX to enhance the treatment of rheumatoid arthritis (RA), poly-articular-course juvenile RA and moderate to severe psoriasis.